As per procedure, the referee stopped play momentarily to talk to the captains and order a message be played over the tannoy system warning the game would be halted if the chants continued.

“This debate is taking a bad turn, because Lazio get seen as a racist club and it is not,” assured President Lotito.

“Unfortunately we cannot control the attitude of individual fans, nor criminalise an entire group of supporters for the behaviour of a few dozen.

“We have to clarify this and punish only those incidents where the majority of the fans take part in racist behaviour.

“I worked hard to prevent this sort of thing happening and I can say our fanbase has changed a lot since I took over as President. However, I cannot put a policeman on every fan when there are 30,000 in the stadium.

“The club has always distanced itself from certain behaviour with words and above all action, taking a strong hand against many fringe elements of the fanbase. We have black players in our squad, it doesn’t make sense for our fans to be racist.”

The chants were from a very small minority and quickly drowned out by the rest of the stadium.

Lazio have a history of far-right elements in their fanbase and were fined earlier this season for racist chanting during a Europa League game with Tottenham.

The rules on how to deal with racist chanting in Italian stadiums is a little unclear. The procedure is to send a message over the tannoy system warning that play will stop if the chants persist.

If they continue, then the referee can stop play for a few minutes. However, it is not clear whether the official can effectively abandon the game due to persistent racist chanting, nor if players can just walk off like Boateng if subjected to abuse.

It remains entirely within the discretion of the referee in Italy and in Europe.